Chemokines are chemotactic cytokines that induce the directed migration of cells by activating specific G protein-coupled receptors. This system of approximately 50 cytokines and approximately 20 receptors plays a particularly prominent role in development, homeostasis and activation of leukocytes in the mammalian immune system. Chemokines determine the nature of the tissue inflammatory response in a wide range of human diseases and represent attractive new therapeutic targets. Chemokines may also attract and stimulate non-immune cells, such as tumor cells, neurons and blood vessels. This meeting will address major unanswered questions in the chemokine field including how Chemokines regulate lymphoid development, how cells sense chemokine gradients, the nature of the chemokine signaling pathway, how Chemokines amplify immunologically-mediated disease, and whether disrupting chemokine signaling can treat or prevent disease. A systems biology approach to chemokine function in vivo will be highlighted and will extend to the regulation and interrelationship of the chemokine system with other regulatory systems in vivo. Directed cell migration is an essential process for normal development, homeostasis and the body's response to infection and cancer. Aberrant cell migration is a critical component of autoimmune and inflammatory diseases. Chemokines and chemokine receptors are the proteins in the body that control the migration of cells. A better understanding of how the chemokine system controls cell movement will lead to new ways of augmenting cell trafficking to fight of infectious diseases, cancer and improve vaccine efficacy as well as inhibit the pathologic recruitment of cells into tissue in autoimmune and inflammatory diseases.